Socialize -- set aside some time each day for a "buddy moment," whether that's grabbing a quick lunch with a co-worker or meeting your sister for some exercise.

Dress for the weather

See the light -- sunlight increases your vitamin D and serotonin levels. In the winter, most northern areas simply do not provide enough natural sunlight to maintain optimal levels, so to get your fill, consider investing in a light box, which can help combat sluggishness. And any day the sun comes out, be sure to pop outside for some rays.

Not many of us enjoy the cold temperatures but for those of us that live in the US now realize that there are indeed communities that have worse winters than you do.

Additionally, many people still believe that being exposed to cold temperatures in and of itself will make you catch a cold, but the evidence points to something entirely different being at work, namely vitamin D deficiency, which just happens to be more prevalent during the winter season.

If you're vitamin D deficient it will not matter much where you live; your chances of coming down with a cold or flu will still increase quite dramatically.

Interestingly enough, these ailments are ALSO affected by your vitamin D status. For more information about how vitamin D can help alleviate those problems, please follow the links provided in the list above.

That said, many if not most of the coldest cities across the United States also tend to be located further North—areas where the days are short and exposure to natural sunlight is scarce this time of year. And that, more than the temperature, can spell disaster for your health.

"The findings of our study support an important role for vitamin D in prevention of common respiratory infections, such as colds and the flu. Individuals with common lung diseases, such as asthma or emphysema, may be particularly susceptible to respiratory infections from vitamin D deficiency."

Several other studies have found an inverse association between lower respiratory tract infections and vitamin D status, meaning, the higher your vitamin D level, the lower your risk of contracting colds, flu, and other respiratory tract infections.

For example:

A 2007 study found that higher vitamin D status enhances your immunity to microbial infections. Subjects with vitamin D deficiency had significantly more days of absence from work due to respiratory infection than did control subjects.

A 2009 study on vitamin D deficiency in newborns with acute lower respiratory infection (ALRI) confirmed a strong, positive correlation between newborns' and mother's vitamin D levels. Over 87 percent of all newborns and over 67 percent of all mothers had vitamin D levels lower than 20 ng/ml, which is a severe deficiency state.

Newborns with vitamin D deficiency appear to have an increased risk of developing ALRI, and since the child's vitamin D level strongly correlates with its mother's, the researchers recommend that all mothers optimize their vitamin D levels during pregnancy, especially in the winter months, to safeguard their baby's health.

A similar Indian study published in 2004 also reported that vitamin D deficiency in infants significantly raised their odds ratio for having severe ALRI.

Another 2009 report in the journal Pediatric Research stated that infants and children appear more susceptible to viral rather than bacterial infections when deficient in vitamin D. And that, based on the available evidence showing a strong connection between vitamin D, infections, and immune function in children, vitamin D supplementation may be a valuable therapy in pediatric medicine.

Sadly, these recommendations do not take into account the amount of vitamin D needed to prevent influenza, heart- or liver- disease, respiratory infections, cancer, or any of the numerous diseases that have a clearly documented link to vitamin D deficiency.

This means the long-term health ramifications of the population at large could be severe, unless the public becomes educated enough to draw their own conclusions.

"Unless these findings are challenged, the public will accept it as true. Doctors, medical institutions, the media, and governmental agencies will all parrot these ultra-low recommendations on vitamin D dosage, pooh-poohing its important therapeutic benefits, and keeping the American public dangerously deficient in the vitamin.

This will mean more colds, more flu, greater dependence on dangerous flu shots and antibiotics, more illness in general, more weak bones, more cancer, and many more deaths. Some experts calculate that proper vitamin D supplementation could save Americans $4.4 trillion over a decade—about $1,346 per person every year."

Vitamin D is More than a Vitamin; It's the "Master Key" to Good Health

"What's shocking to me is that the levels they are recommending will not even approximate what you would get if you were exposed to healthy levels of sunshine," Dr. Cannell says.

From an evolutionary perspective, evaluating the vitamin D levels early man produced from natural sun exposure would indeed be a more appropriate way to analyze our optimal vitamin D requirements, because the human genome was designed for a certain level of sun exposure.

In fact, vitamin D is the only known substrate for a potent, pleiotropic (meaning it produces multiple effects) repair and maintenance seco-steroid hormone that serves multiple gene-regulatory functions in your body.

As explained by vitamin D expert Dr. Heaney, each cell in your body has its own DNA library that contains information needed to deal with virtually every kind of stimulus it may encounter, and the master key to enter this library is activated vitamin D.

Hence, without sufficient amounts of vitamin D, your cells cannot access their DNA libraries, and their functions are thereby impaired.

This is why vitamin D functions in so many different tissues, and affects such a large number of different diseases and health conditions, including at least 16 different types of cancer.

So far, scientists have found about 3,000 genes that are upregulated by vitamin D, and researchers keep finding health benefits from vitamin D in virtually every area they look.

A European meta-analysis published in the Archives of Internal Medicinein 2007 even found that increased vitamin D levels can lower your risk of dying from any cause!

Vitamin D also acts as a potent natural antibiotic by increasing your body's production of proteins called antimicrobial peptides. Antimicrobial peptides destroy the cell walls of bacteria, fungi, and viruses, including the influenza virus, which explains why it's such a potent prevention strategy against cold and flu.

Sadly, none of these findings appear to have been considered by the IOM vitamin D panel.

But why?

The IOM's "Expert" Vitamin D Panel Did Not Include Vitamin D Experts!

You'd think that the IOM's vitamin D panel would consist of first-rate vitamin D experts but that's actually not the case.

According to Carol Baggerly, a number of well-respected vitamin D researchers were recommended to the panel but were explicitly rejected—a fact she calls "disturbing."

In my recent interview with her, Baggerly also explained that the IOM panel was very selective about the data they chose to review, excluding a wide variety of very important data. For example, they did not review any epidemiological data at all according to Baggerly, despite the fact that there are "decades of research substantiating that people die of all kinds of diseases that are impacted by vitamin D."

Clearly, had such data been included, it would have been impossible to justify their current position.

One of the Best New Year's Resolutions You Can Make—Optimize Your Vitamin D Levels!

I would strongly urge you to make it your New Year's resolution to optimize your vitamin D levels this winter and see if you can't avoid all colds, coughs, and flus.

I'm willing to bet that once you get into the optimal range—as opposed to the prescribed "normal"— colds and flus will be a thing of the past.

Since it's winter and sunlight is scarce, the ideal way to optimize your vitamin D levels would be to either use a safe tanning bed or take an oral vitamin D3 supplement. Below are the recommended oral dosages based on the research available (which the IOM chose to ignore).

Vitamin D Dose Recommendations

Age

Dosage

Below 5

35 units per pound per day

Age 5 - 10

2500 units

Adults

5000 units

Pregnant Women

5000 units

WARNING: There is no way to know if the above recommendations are correct for you personally. The ONLY way to know is to test your blood. You might need 4-5 times the amount recommended above. Ideally your blood level of 25 OH D should be 60ng/ml.

Keep in mind, however, that you need to get your vitamin D levels tested prior to taking an oral vitamin D supplement, and regularly recheck it thereafter to ensure your levels are maintained within the optimal range of 50-70 ng/ml.

Both the Vitamin D Council and GrassrootsHealth recommend maintaining a vitamin D level of at least 40 ng/ml, at bare minimum.

This minimum optimal range is a far cry from the IOM's recommended vitamin D blood serum level of just 20 ng/ml. Based on more appropriate parameters for optimal health, 20 ng/ml actually signifies a state of severe deficiency!

To me, it borders on criminal negligent malpractice to ignore the abundance of scientific evidence that suggest that the deficiency levels are far above 20 ng/ml.

Do Your Own Research

Always remember that you have the freedom to do your own research and are not obligated in any way to adhere to "government sanctioned" nutrient recommendations.

A good place to start is my vitamin D index page, which links to all of the latest vitamin D information posted on my site.

In this case, it's quite clear that the IOM has flat-out ignored the science available on vitamin D. So, if what the Vitamin D Council and I have been posting about the health benefits of vitamin D and the optimal vitamin D levels make sense to you, then you can choose to ignore the recommendations from the Institute of Medicine.

I've been a long-time proponent for safe and sensible sun exposure to optimize vitamin D levels, and I maintain my vitamin D level within the optimal-high range year-round.

I firmly believe it's one of the most powerful preventive strategies there is for colds and flus. But you don't have to take my word for it. Try it out for yourself!

Make 2011 the year when you optimize your vitamin D levels to improve your health, and see what happens. I believe you'll be pleasantly surprised!